According to government evidence, on Dec. 30, 2011, Coates and an accomplice forced Studevant into Marvin Gaye Park in Northeast D.C., where they punched and kicked him. Studevant broke free and ran across the park, but Coates and the accomplice caught him.

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Prosecutors say Coates stabbed Studevant with a knife, then choked Studevant with his belt.

Studevant was found unconscious near a creek around 8 a.m. on Dec. 31 and pronounced dead at the scene.

Coates and the accomplice split money they took from Studevant's wallet, prosecutors say.

Studevant had been a vendor at Eastern Market, selling bottled water and newspapers. His death was considered the first homicide of 2012 because the Office of the Chief Medical Examiner didn't rule on Studevant's cause of death until Jan. 1, 2012.